Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.

"People think everybody has premarital doubts and you don't have to worry about them," Justin Lavner, a UCLA doctoral student in psychology who led the study, said in a statement. "We found they are common but not benign. Newlywed wives who had doubts about getting married before their wedding were two-and-a-half times more likely to divorce four years later than wives without these doubts. Among couples still married after four years, husbands and wives with doubts were significantly less satisfied with their marriage than those without doubts."

Lavner and his team studied 232 couples in Los Angeles during the first few months of marriage and then checked in on the spouses every six months for four years.

During the first interview, the researchers asked the newlyweds, "Were you ever uncertain or hesitant about getting married?" Forty-seven percent of husbands answered "yes," compared with 38 percent of wives. While men seemed more likely to have cold feet, their wives' reservations better predicted future problems.

Nineteen percent of wives who reported doubts about getting married were divorced four years later. Among women who did not report doubts, just 8 percent were divorced four years later. For husbands, those figures were 14 percent and 9 percent, respectively.

In 36 percent of couples, both partners said they had no doubts before the wedding, and of those, just 6 percent got divorced by the four-year mark. Among couples in which both spouses reported premarital doubts, 20 percent got divorced. Of couples in which only the husband reported doubts, 10 percent got divorced, compared with 18 percent of couples who got divorced when only the wife had doubts. Past research, detailed in the December 2011 issue of the journal Family Relations, found that fear of divorce actually keeps many devoted young couples from saying "I do."

Doubts, however, don't necessarily mean doom for the relationship, Lavner and his team assured. But the researchers, who published their study in the Journal of Family Psychology, recommended that couples address misgivings before tying the knot.

"If you see something unusual on your skin, should you ignore it and go to the beach, or see a doctor? Be smart and don't ignore it — and don't ignore your doubts either," researcher Thomas Bradbury, who co-directs the Relationship Institute at UCLA, said in a statement. "Have a conversation and see how it goes. Do you think the doubts will go away when you have a mortgage and two kids? Don't count on that."

In fact, a record number of Americans are unmarried today, research reported in 2011 by the Pew Research Center, though the researchers aren't sure if people are delaying marriage or shunning it altogether; the survey did show the proportion of never-married Americans has doubled since 1960.